U.S. patent application number 11/274659 was filed with the patent office on 2006-04-13 for ultrasonic platform type microchip and method of driving array-shaped ultrasonic transducers.
This patent application is currently assigned to OLYMPUS CORPORATION. Invention is credited to Miyuki Murakami.
Application Number | 20060078473 11/274659 |
Document ID | / |
Family ID | 33455493 |
Filed Date | 2006-04-13 |
United States Patent
Application |
20060078473 |
Kind Code |
A1 |
Murakami; Miyuki |
April 13, 2006 |
Ultrasonic platform type microchip and method of driving
array-shaped ultrasonic transducers
Abstract
The present invention provides a micro chemical analysis system
in which a flow type microchip configured to have a fine flow
passage on a substrate is configured, the system comprising a
common platform composed of a transducer layer and a signal control
circuit layer, the transducer layer having array-shaped ultrasonic
transducers. In addition, the flow type microchip is configured on
the common platform.
Inventors: |
Murakami; Miyuki; (Hino-shi,
JP) |
Correspondence
Address: |
Scully, Scott, Murphy & Presser
400 Garden City Plaza
Garden City
NY
11530-3319
US
|
Assignee: |
OLYMPUS CORPORATION
TOKYO
JP
|
Family ID: |
33455493 |
Appl. No.: |
11/274659 |
Filed: |
November 15, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP04/06813 |
May 13, 2004 |
|
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11274659 |
Nov 15, 2005 |
|
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Current U.S.
Class: |
422/400 |
Current CPC
Class: |
B01L 3/502738 20130101;
B01L 2300/0867 20130101; B01L 2300/0819 20130101; B01L 2400/0439
20130101; F04B 19/006 20130101; B01L 2300/0816 20130101; B01L
2400/0496 20130101; B01L 3/502792 20130101; B01L 3/50273 20130101;
B01L 3/502746 20130101 |
Class at
Publication: |
422/100 |
International
Class: |
B01L 3/00 20060101
B01L003/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 16, 2003 |
JP |
2003-139168 |
May 16, 2003 |
JP |
2003-139170 |
Claims
1. An ultrasonic platform type microchip which is a flow type
microchip for use in a micro chemical analysis system, configured
to have a fine flow passage in which a fluid flows on a substrate,
the microchip comprising: a common platform composed of a
transducer layer and a signal control circuit layer, the transducer
layer having array-shaped ultrasonic transducers, wherein the flow
type microchip is configured on the common platform.
2. An ultrasonic platform type microchip according to claim 1,
wherein the transducer layer and the signal control circuit layer
of the common platform are fabricated on one substrate in
accordance with a semiconductor process.
3. An ultrasonic platform type microchip according to claim 1,
wherein the transducer layer and the signal control circuit layer
of the common platform each are produced on individual substrates,
and then, are assembled by means of adhesive or bonding in a state
in which conductivity of each layer has been established.
4. An ultrasonic platform type microchip according to claim 1,
wherein the control circuit layer is composed of an electric
circuit layer fabricated in accordance with a semiconductor
process.
5. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a capacitive
micromachined micro ultrasonic transducer.
6. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a transducer
fabricated in accordance with an ejection deposition technique.
7. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a transducer
fabricated in accordance with a sol-gel technique.
8. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a transducer
fabricated in accordance with a water and heat synthesis
technique.
9. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a transducer
fabricated in accordance with a sputtering technique.
10. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is composed of a transducer
fabricated in accordance with a printing technique.
11. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer later is configured in direct
contact with the flow passage of the flow type microchip.
12. An ultrasonic platform type microchip according to claim 1,
wherein an acoustic matched layer is formed between the common
platform and the flow passage of the direct flow type
microchip.
13. An ultrasonic platform type microchip according to claim 12,
wherein the acoustic matched layer is composed of porous silicon
made porous by anode synthesis of silicon.
14. An ultrasonic platform type microchip according to claim 12,
wherein the flow type microchip is composed of a resin which is
obtained as an acoustic matched layer in itself.
15. An ultrasonic platform type microchip according to claim 12,
wherein the flow type microchip has an acoustic lens provided in an
acoustic matched layer of a site which comes into contact with the
fluid contained therein.
16. An ultrasonic platform type microchip according to claim 1,
wherein a drive signal is supplied to a plurality of ultrasonic
transducers disposed along the flow passage of the flow type
microchip such that a radiation sound pressure increases from an
inlet of the flow passage toward an outlet of the flow passage,
thereby generating a flow of a fluid oriented from the inlet of the
flow passage to the outlet of the flow passage.
17. An ultrasonic platform type microchip according to claim 1,
wherein a drive signal is supplied to a plurality of ultrasonic
transducers disposed along the flow passage of the flow type
microchip while sound wave radiation times are shifted from an
input of the flow passage to an outlet of the flow passage, thereby
generating a flow of a fluid oriented from the inlet of the flow
passage toward the outlet of the flow passage.
18. An ultrasonic platform type microchip according to claim 1,
wherein a drive signal, whose frequency is at a wavelength which is
sufficiently shorter than flow passage dimensions and is obtained
as a high radiation sound pressure, is supplied to an ultrasonic
transducer disposed immediately beneath the flow passage of the
flow type microchip, thereby controlling a flow rate in a
predetermined flow passage.
19. An ultrasonic platform type microchip according to claim 1, the
microchip having a liquid housing cell which is greater than a
width of the flow passage in the flow type microchip, wherein a
drive signal is supplied in irregular sequence to a plurality of
ultrasonic transducers disposed at a lower part of the liquid
housing cell in a two-dimensional matrix shape, thereby stirring
and mixing the liquid contained in the liquid housing cell.
20. An ultrasonic platform type microchip according to claim 1,
further comprising: a wave transmission ultrasonic transducer
provided at a flow passage inlet side of the flow type microchip; a
wave reception ultrasonic transducer disposed to be spaced from the
wave transmission ultrasonic transducer to a flow passage outlet
side at a predetermined distance; an ultrasonic flow velocity gauge
which obtains a flow velocity by measuring a time required for a
tone burst wave wave-transmitted from the wave transmission
ultrasonic transducer to be sensed by the wave receiving sound wave
transducer.
21. An ultrasonic platform type microchip according to claim 1,
further comprising: a wave transmission ultrasonic transducer
provided at a flow passage inlet side of the flow type microchip; a
wave reception ultrasonic transducer disposed to be spaced from the
wave transmission ultrasonic transducer to a flow passage outlet
side at a predetermined distance; an ultrasonic temperature gauge
which obtains a temperature by measuring a time required for a tone
burst wave wave-transmitted from the wave transmission ultrasonic
transducer to be sensed by the wave receiving sound wave
transducer.
22. An ultrasonic platform type microchip according to claim 1,
wherein the ultrasonic transducer is an ultrasonic transducer which
vibrates parallel to the flow passage of the flow type microchip,
and the ultrasonic transducer configures part of a resonator
circuit and detects viscosity of a fluid from a resonance frequency
change of the resonator circuit.
23. An ultrasonic platform type microchip according to claim 1,
wherein the flow type microchip is composed of a transparent
material, the signal control circuit layer has a photodetector at a
potion thereof; the transducer layer has a through hole above the
photo detector, and optical measurement is carried out with respect
to light irradiated from a top surface of the flow passage of the
flow type microchip on which the photodetector has been provided
upwardly.
24. An ultrasonic platform type microchip according to claim 1,
wherein the common platform is configured to have a plurality of
fluid measurement control elements on one substrate.
25. An ultrasonic platform type microchip according to claim 1,
wherein the common platform is configured to be divided every fluid
measurement control element and to be arbitrarily combined.
26. A method of driving array-shaped ultrasonic transducers
configured beneath a flow type microchip configured to have a fine
flow passage on a substrate, the method comprising: selectively
inputting a desired drive signal to the ultrasonic transducer such
that a sound pressure in the flow passage increases from an input
of the flow passage toward an outlet of the flow passage.
27. A method of driving array-shaped ultrasonic transducers
configured beneath a flow type microchip configured to have a fine
flow passage on a substrate, the method comprising: selectively
inputting a desired drive signal to the ultrasonic transducer such
that a sound pressure increases from an input of the flow passage
toward an outlet of the flow passage by shifting ultrasonic
radiation times of the ultrasonic transducers.
28. A method of driving array-shaped ultrasonic transducers
configured beneath a flow type microchip configured to have a fine
flow passage on a substrate, the method comprising: selectively
inputting a desired drive signal to the ultrasonic transducer such
that a sound pressure locally increases between an inlet of the
flow passage and an outlet of the flow passage.
29. A method of driving array-shaped ultrasonic transducers
configured beneath a flow type microchip configured to have a fine
flow passage on a substrate, the method comprising: selectively
inputting a desired drive signal to the ultrasonic transducer such
that a plurality of fluids having different physical properties or
states exist in the flow passage and that a flow is generate in a
direction crossing an interface of said plurality of fluids.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a Continuation Application of PCT Application No.
PCT/JP2004/006813, filed May 13, 2004, which was published under
PCT Article 21(2) in Japanese.
[0002] This application is based upon and claims the benefit of
priority from prior Japanese Patent Applications No. 2003-139168,
filed May 16, 2003; and No. 2003-139170, filed May 16, 2003, the
entire contents of both of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to a flow type microchip
having a micro flow passage on a substrate. More particularly, the
present invention relates to an ultrasonic platform type microchip
wherein a flow type microchip having a flow passage according to
its purpose formed thereon has been configured on a common platform
which is composed of a transducer layer and a signal control layer,
the transducer layer having array-shaped ultrasonic transducers,
and a variety of functions are achieved with respect to a fluid by
signal-controlling an arbitrary ultrasonic transducer, and a method
of driving an ultrasonic transducer in the chip.
[0005] 2. Description of the Related Art
[0006] In recent years, the fields of biotechnology, environmental
technology, and information technology (IT) have focused attention
as the fields of application of micro-electromechanical systems
(MEMS) technology. As its specific application, research has been
actively conducted worldwide, the research integrating functions
required for chemical analysis or chemical synthesis by using a
micro machining technique on a glass or a silicon substrate of some
tens of millimeters in cube, and promoting downsizing of the
chemical analysis or a synthetic system itself.
[0007] This research field is called micro total analysis systems
(.mu.TAS), and has a plenty of features as described below, as
compared with a conventional analysis device for use in
experimental room. That is, the features include: enabling
achievement of a high speed analysis time; enabling downsizing or
portability of an analysis device; enabling reduction of a solvent
or a sample to be consumed; and enabling reduction of analysis
cost. This research field is expected as a new technology for
inexpensive analysis through high throughput on the site of medical
applications or environment measurement. In particular, it is
expected to downsize the smallest chemical system which has been of
a table top size to a palm size by expanding it to a system having
a sensor or an electronic circuit integrated on a .mu.TAS chip, in
addition to a flow passage or a pump for the sake of chemical
reaction.
[0008] Many of conventionally proposed .mu.TAS chips are flow type
microchips which carry out stirring, mixing, reaction, sampling and
the like while flowing a fluid on the chips. For example, a micro
capillary electrophoresis chip which generates a high voltage
gradient on a flow passage to move a fluid, which carries out
preprocessing or separation, and which carries out non-contact
conductivity measurement of a biological substance on a single
substrate is known by "Micro Total Analysis Systems 2002, pages 491
to 493, `Separation and detection of organic scids in a CE
microchip with contactless four-electrode conductivity detection`".
Since only a micro flow passage is formed on a capillary
electrophoresis chip, a structure and fabrication of a chip itself
are facilitated.
[0009] In addition, with respect to a microchip pileup type
chemical reaction system, for example, Jpn. Pat. Appln. KOKAI
Publication No. 2002-292275 discloses a chemical reaction system
having a configuration in which there are laminated and integrated
a predetermined number of microchips, each of which comprises a
reaction material solution introducing section, a reaction product
solution discharge section, and a micro channel serving as a
reaction region communicating with these sections. Only a
microchannel (micro flow passage) is formed on each chip of this
system. The flow passage is designed so as to efficiently carry out
a variety of reactions such as a chain-shaped reaction, a solvent
sampling, an immunoreaction, an enzyme reaction, and an ion pair
sampling reaction by utilizing an advantage such as a short
molecule scattering distance or a large specific interface area
which is a chemical reaction field. This chemical reaction system
enables mass organic synthesis with high efficiency by laminating
and integrating chips parallel to each other.
[0010] Further, with respect to a chemically integrated circuit and
a method of manufacturing the circuit, Jpn. Pat. Appln. KOKAI
Publication No. 2001-158000 discloses a chemical reaction circuit
which is configured by forming a single functional chip in which a
plurality of parts having the same function and the same mechanism
are disposed in one chip by utilizing an optical molding technique,
and by combining chips having different single functions with each
other in a plurality of layers. In this publication, a single
purpose type chemical IC having incorporated therein all functions
required for one microchip has a problem in terms of general
purpose property, quick responsiveness, and functional upgrading
property. In contrast, the optical molding technique .mu.TAS is
suitable to high-mix low-volume production or individual
production, and is superior in terms of manufacturing time and cost
efficiency.
[0011] As a specific example, there is described a chemical
integrated circuit in which there are laminated and coupled four
chips consisting of: a first layer chip which is a "connector tube"
having external and fluid input and output connectors; a second
layer chip which is a "valve chip"; a third layer chip which is a
"reactor chip"; and a fourth layer which is a "condensed chip",
making it possible to achieve one purpose.
[0012] Further, with respect to a flow control method in a
microsystem, Jpn. Pat. Appln. KOKAI Publication No. 2002-163022
discloses a microsystem for introducing a sol-gel transiting
substance with a stimulus into a fluid which flows in a micro flow
passage of the microsystem, applying a stimulus to a desired site
on the micro flow passage, and gelling the fluid, thereby
controlling the flow. According to this system, it becomes possible
to stop the flow of the fluid in the micro system or adjusting a
flow rate or a flow speed without using a complicated valve
structure on a microchip.
[0013] In the case of the capillary electrophoresis chip based on
the technique described previously, the items of reaction and
analysis which can be carried out on the chip are very limited. In
addition, an electrode for generating a high voltage gradient in a
flow passage is externally inserted into the flow passage, and
comes into direct contact with the fluid. Thus, there are provided
problems that an electrochemical reaction is prone to occur in the
vicinity of the electrode, and that a biochemical substance is
probe to be refined.
[0014] Moreover, in the case of the microchip in the microchip
pileup type chemical reaction system as described in Jpn. Pat.
Appln. KOKAI Publication No. 2002-292275, a configuration for
carrying out a variety of reactions and samplings is provided by
only a microchannel (micro flow passage). Therefore, a microchannel
design (such as width, depth, and length) must be finely changed
according to a fluid to be utilized or its purpose. Additionally,
in the case of the microchip (flow passage) in such a microchip
pileup type chemical reaction system, there are provided problems
that there is a need for an external mechanism (pump) for
transporting a fluid, and that quantitative fluid sampling cannot
be carried out.
[0015] On the other hand, in the case of the chemical integrated
circuit as described in Jpn. Pat. Appln. KOKAI Publication No.
2001-158000, a variety of microchips are molded in accordance with
an optical molding technique. Accordingly, it is difficult to
fabricate them as finely as parts such as in a semiconductor
process with respect to a flow passage as well as parts such as
valves or connectors, and thus, a variety of advantages in molecule
scattering distance, specific interface area, and thermal capacity
represented by a liquid layer microspace are reduced. In addition,
since the optical molding technique requires a large amount of
processing time as compared with a silicon process capable of
mass-producing specific microcircuits, higher cost per chip is
unavoidable.
[0016] In the microsystem utilizing sol-gel transition of a fluid
as described in Jpn. Pat. Appln. KOKAI Publication No. 2002-163022,
the composition of the fluid somewhat changes because a sol-gel
transiting substance (in general, polymeric compound) is introduced
into the fluid. This has affected a result of reaction, sampling,
or analysis.
BRIEF SUMMARY OF THE INVENTION
[0017] Therefore, it is an object of the present invention to
provide an ultrasonic platform type microchip and a method of
driving array-shaped ultrasonic transducers, wherein the microchip
can be manufactured within a short manufacturing time and at a low
cost while maintaining its general purpose usability, quick
responsiveness, and functional upgrading property without changing
a fluid composition and without degrading a variety of advantages
represented by a liquid layer microspace.
[0018] A first feature of the present invention is an ultrasonic
platform type microchip which is a flow type microchip for use in a
micro chemical analysis system, configured to have a fine flow
passage in which a fluid flows on a substrate, the microchip
comprising:
[0019] a common platform composed of a transducer layer and a
signal control circuit layer, the transducer layer having
array-shaped ultrasonic transducers,
[0020] wherein the flow type microchip is configured on the common
platform.
[0021] A second feature of the present invention is a method of
driving array-shaped ultrasonic transducers configured beneath a
flow type microchip configured to have a fine flow passage on a
substrate, the method comprising:
[0022] selectively inputting a desired drive signal to the
ultrasonic transducer such that a sound pressure in the flow
passage increases from an input of the flow passage toward an
outlet of the flow passage.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0023] FIG. 1 is a sectional view showing a first embodiment of the
present invention and showing a basic configuration of an
ultrasonic platform type micro chemical analysis system according
to the invention.
[0024] FIG. 2 is a plan view of a transducer layer in FIG. 1.
[0025] FIG. 3 is a plan view showing an aspect of the ultrasonic
platform type micro chemical analysis system, wherein transparent
flow type microchips are laminated on the transducer layer.
[0026] FIG. 4 is a sectional view of the ultrasonic platform type
micro chemical analysis system in FIG. 3.
[0027] FIG. 5 is a view illustrating an operation of a "pump" which
is a first function of the first embodiment.
[0028] FIG. 6 is a view illustrating another operation of the
"pump" which is the first function of the first embodiment.
[0029] FIG. 7 is a view illustrating an operation of the "pump"
which is the first function of the first embodiment and showing an
example in which ultrasonic transducers have been disposed
immediately beneath a microchip flow passage along the flow
passage.
[0030] FIG. 8 is a view illustrating an operation of the "pump"
which is the first function of the first embodiment and showing an
example in which ultrasonic transducers have been disposed
immediately beneath a microchip flow passage along the flow
passage.
[0031] FIG. 9 is a view illustrating an operation of the "pump"
which is the first function of the first embodiment and showing an
example in the case of using an ultrasonic transducer for
generating a surface acoustic wave.
[0032] FIG. 10 is a view illustrating an operation of the "pump"
which is the first function of the first embodiment and showing
another example in the case of using the ultrasonic transducer for
generating the surface acoustic wave.
[0033] FIG. 11 is a view illustrating an operation of a "valve"
which is a second function of the first embodiment.
[0034] FIG. 12 is a view illustrating an operation of the "valve"
which is the second function of the first embodiment.
[0035] FIG. 13 is a view illustrating an operation of the "valve"
which is the second function of the first embodiment.
[0036] FIG. 14 is a view illustrating an operation of the "valve"
which is the second function of the first embodiment and showing
another configuration example.
[0037] FIG. 15 a view illustrating an operation of the "valve"
which is the second function of the first embodiment and
illustrating the configuration example of FIG. 14.
[0038] FIG. 16 is a view illustrating an operation of a
"temperature gauge" which is a third function of the first
embodiment.
[0039] FIG. 17 is a view illustrating an operation of the
"temperature gauge" which is the third function of the first
embodiment and showing a change state of a tone-burst wave.
[0040] FIG. 18 is a view illustrating an operation of the
"temperature gauge" which is the third function of the first
embodiment.
[0041] FIG. 19 is a characteristic view illustrating an operation
of the "temperature gauge" which is the third function of the first
embodiment, and showing flow velocity characteristic.
[0042] FIG. 20 is a view illustrating an operation of a "mixer"
which is a fourth function of the first embodiment.
[0043] FIG. 21 is a view illustrating another example of the first
embodiment and an operation of an optical absorption gauge using a
photodiode.
[0044] FIG. 22 is a view illustrating another example of the first
embodiment and an operation of an optical absorption gauge using a
photodiode.
[0045] FIG. 23 is a view showing a still another configuration
example according to the first embodiment.
[0046] FIG. 24 is a view showing a still another configuration
example according to the first embodiment and showing a temperature
characteristic.
[0047] FIG. 25 is a sectional view showing a modified example of
the first embodiment.
[0048] FIG. 26 is a sectional view showing another modified example
of the first embodiment.
[0049] FIG. 27 is a sectional view showing still another modified
example of the first embodiment.
[0050] FIG. 28 is a view showing a second embodiment according to
an ultrasonic platform type micro chemical analysis system of the
present invention.
[0051] FIG. 29 is a view showing a third embodiment according to
the ultrasonic platform type micro chemical analysis system of the
present invention.
[0052] FIG. 30 is a view showing an example of a configuration of
the ultrasonic platform type micro chemical analysis system of the
third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0053] Hereinafter, embodiments of the present invention will be
described with reference to the accompanying drawings.
[0054] In an ultrasonic platform type microchip according to the
invention, a fluid is measured and controlled by means of an
ultrasonic wave. The ultrasonic wave has features that: (1) even if
a film or a plate exists, an ultrasonic wave can transmit the film
or plate as long as acoustic matching is obtained; and (2) there
can be excited a phenomenon caused by sound non-linearity even with
a small amount of acoustic power by increasing a frequency.
[0055] Hereinafter, referring to the accompanying drawings, a
detailed description will be given for an embodiment of an
ultrasonic platform type micro chemical analysis system using the
ultrasonic platform according to the invention.
[0056] FIG. 1 is a sectional view showing a first embodiment of the
present invention and showing a basic configuration of the
ultrasonic platform type micro chemical analysis system according
to the invention. FIG. 2 is a plan view of a transducer layer in
FIG. 1. FIG. 3 is a plan view showing an aspect of the ultrasonic
platform type micro chemical analysis system, wherein transparent
flow type microchips are laminated on the transducer layer. FIG. 4
is a sectional view of the ultrasonic platform type micro chemical
analysis system in FIG. 3.
[0057] In FIGS. 1 and 2, the first embodiment of the invention is
configured as follows.
[0058] A basic ultrasonic platform type micro chemical analysis
system 10 shown in FIG. 1 is configured to have: one common
platform 16 having a signal control circuit layer 12 and a
transducer 14; and a transparent flow type microchip 18 configured
on the common platform 16.
[0059] The signal control circuit layer 12 has a plurality of
processor circuits incorporated therein. The transducer layer 14
has a plurality of array-shaped ultrasonic transducers 22 disposed
along a direction in which a fluid flows, as shown in FIG. 2. The
ultrasonic transducer 22 can convert an input voltage to a
vibration (ultrasonic wave) or can convert an inputted vibration to
a voltage. In addition, the array-shaped ultrasonic transducer 22
is connected to the processor circuit 20 contained in a signal
control circuit layer by wires 24, whereby conductivity of the
transducer layer 14 is established. Consequently, the system 10 is
configured so as to enable signal control such as driving or
sensing relevant to a predetermined ultrasonic transducer. The
common platform 16 can be configured in accordance with a
semiconductor process.
[0060] The flow type microchip 18 is composed of a resin, a glass
or the like. Then, a flow passage 28 according to its purpose is
formed at the inside of the flow type microchip 18. The flow
passage 28 is fixed onto a common platform after fabricated on a
resin substrate apart from the common platform.
[0061] FIGS. 3 and 4 are views each showing an aspect of the
ultrasonic platform type micro chemical analysis system in
accordance with the first embodiment. This is a chemical analysis
system which measures optical absorption having a predetermined
wavelength while monitoring a fluid temperature after two reagents
and one sample have been stirred and mixed quantitatively.
[0062] In addition to the basic configuration of the ultrasonic
platform type micro chemical analysis system, the embodiment is
configured to have a photodetector 32 in part of the signal control
circuit layer 12 of the common platform 16. The common platform 16
is formed on a silicon substrate in accordance with a semiconductor
process.
[0063] In addition, on the signal control circuit layer 12 in the
common platform 16, a plurality of capacitive micromachined
ultrasonic transducers (cMUT) disposed in a two-dimensional array
shape are formed on the same substrate as a transducer layer
14.
[0064] A plurality of processor circuits 20 and a photodetector 32
are arranged in the signal control circuit layer 12. A plurality of
array-shaped ultrasonic transducers 22 are provided in the
transducer layer 14. The transducers 22 are connected to the
processor circuits 20 by the wires 24.
[0065] In addition, a through hole 14a is formed at the upper part
of a portion of the photodetector 33 in the transducer layer 14.
The transducer layer 14 establishes conductivity with the signal
control circuit layer 12 by the wires 24, and is configured to
enable signal control of a predetermined cMUT.
[0066] Further, at the microchip side, an acoustic matching layer
34 composed of, for example, porous silicon made porous by anode
chemical synthesis of silicon is provided on the transducer layer
14. A flow passage layer 36 and a flow passage 38 are formed on the
acoustic matching layer 34. Moreover, a cover 40 is provided on the
flow passage layer 36 and flow passage 38.
[0067] As shown in FIG. 3, in an ultrasonic platform type micro
chemical analysis system 30 according to the embodiment, the flow
passage 38 in the microchip is constructed at a position such that
an arbitrary ultrasonic transducer 22 of the transducer layer 14
irradiates a fluid with an ultrasonic wave and generates a
distribution of sound pressure strengths in a direction in which
the fluid flows, thereby making it possible to achieve the
following four functions.
[0068] A first function is a "pump" which moves a fluid along a
flow passage, and a second function is a "valve" which controls a
flow rate of the fluid. Further, a third function is a "temperature
gauge" which detects a fluid temperature, and a fourth function is
a "mixer" which stirs and mixes different types of fluids. All the
four functions are achieved by selectively inputting a desired
drive signal to the arbitrary ultrasonic transducer 22 in the
transducer layer 14.
[0069] For example, in the ultrasonic platform type micro chemical
analysis system 30 shown in FIG. 3, there are provided at the
upstream side of the flow passage 38: a first reagent inlet (flow
passage inlet) 42a and a second regent inlet 42b for use as reagent
inlets; and a sample inlet 44 for use as a sample inlet. On the
other hand, one outlet (flow passage outlet) 46 is provided at the
downstream side of the flow passage 38.
[0070] From among the ultrasonic transducers 22 disposed in an
array shape, a pump transducer 22a serving as the first function
described previously is disposed along the flow passage 38. In
addition, a mixing transducer 22d serving as the fourth function is
disposed at the substantial center portion of the flow passage
38.
[0071] Moreover, valve transducers 22b each serving as the second
function are disposed at the upstream side of a branch site of the
flow passage 38 and at the downstream side of the mixing transducer
22d. Temperature gauge transducers 22c each serving as the third
function are disposed at the downstream side of the branch site of
the flow passage 38, at the upstream side and downstream side of
the mixing transducer 22d, and at the upstream side of the outlet
46.
[0072] At the downstream side of the outlet, the photodetector 32
is provided beneath the flow passage 38.
[0073] Now, an operation of the first embodiment of the invention
will be described here.
[0074] First, an operation of a "pump" which is the first function
will be described with reference to FIGS. 5 and 6.
[0075] Here, for the sake of simplification, the ultrasonic
platform type micro chemical analysis system, as shown in FIG. 5,
is configured so that "n" ultrasonic transducers 50.sub.1,
50.sub.2, . . . , 50.sub.n and 52.sub.1, 52.sub.2, . . . , 52.sub.n
have been disposed respectively at both of the outsides of the flow
passage 38 having the inlet 44 and the outlet 46.
[0076] At the lower part of the microchip, the "n" ultrasonic
transducers 50.sub.1, 50.sub.2, . . . , 50.sub.n and 52.sub.1,
52.sub.2, . . . , 52.sub.n disposed along both of the outsides of
the flow passage 38 are driven at the same time at each of
predetermined signals. At this time, a signal to be supplied to
each of the ultrasonic transducers 50.sub.1, 50.sub.2, . . . ,
50.sub.n and 52.sub.1, 52.sub.2, . . . , 52.sub.n is set so that
drive voltages increase in sequence such that each radiation sound
pressure has a relationship of the transducer 50.sub.1 near the
inlet 44 (52.sub.1)<the transducer 50.sub.2 (52.sub.2)< . . .
<the transducer 50.sub.n (52.sub.n) near the outlet 46. Each of
the ultrasonic transducers 50.sub.1, 50.sub.2, . . . , 50.sub.n and
52.sub.1, 52.sub.2, . . . , 52.sub.n vibrates in response to a
drive signal, and radiates an ultrasonic wave in a direction which
is different from the direction in which the fluid flows.
[0077] As shown in FIG. 6, the ultrasonic wave radiated from each
of the ultrasonic transducers generates an acoustic flow (straight
flow) in a direction distant from a sound source in accordance with
its non-linearity. At this time, the acoustic flow is bent in a
direction in which the sound pressure is high, due to eccentricity
(distribution) in balance of the sound pressure strength of the
adjacent transducers. Thus, macroscopically, a flow field oriented
from the inlet 44 to the outlet 46 is formed.
[0078] That is, at the lower part of the microchip, a voltage
applied to at least one ultrasonic wave transmission means as
described previously is made different from a voltage applied to
the remaining ultrasonic carrying means by means of the "n"
ultrasonic transducers disposed along both of the outsides of the
flow passage. Alternatively, the function of "pump" which moves a
fluid along a flow passage can be achieved by making the sound
pressure strength near the at least one ultrasonic wave
transmission means different from the sound pressure strength near
the remaining ultrasonic wave transmission means.
[0079] In addition, such a "pump" function, as shown in FIG. 7, can
be achieved by "n" ultrasonic transducers 54.sub.1, 54.sub.2, . . .
, 54.sub.n disposed along the flow passage 38 immediately beneath
the microchip flow passage 38.
[0080] Further, the "n" ultrasonic transducers disposed along the
flow passage are driven at the same time by means of each of
predetermined signals. At this time, as shown in FIG. 8, drive
signals are supplied to each of the ultrasonic transducers
54.sub.1, 54.sub.2, . . . , 54.sub.n while sound wave radiation
times are shifted, in sequence such that the radiation sound
pressures have a relationship of the transducer 54.sub.1 near the
inlet 44<the transducer 54.sub.2< . . . <the transducer
54.sub.n near the outlet 46.
[0081] Although an acoustic flow (straight flow) is generated in a
direction distant from a sound source by means of the ultrasonic
wave radiated from each of the transducers, a sound field formed in
a flow passage is changed with an elapse of time by shifting sound
wave generation times of the adjacent transducers. Thus, the
acoustic flow is bent in a direction in which a sound pressure is
high at each time, and the flow field oriented from the inlet 44 to
the outlet 46 can be formed on time average manner. That is, the
function of "pump" can be achieved by means of time control as
well.
[0082] Further, even in the case of using an ultrasonic transducer
for generating a surface acoustic wave (SAW), the function of
"pump" can be achieved, as shown in FIGS. 9 and 10, by setting a
drive signal so that a vibration amplitude at a certain time
increases in sequence such that the transducer 54.sub.1 near the
inlet 44<the transducer 54.sub.2< . . . <the transducer
54.sub.n near the outlet 46.
[0083] Now, an operation of the "valve" which is the second
function will be described with reference to FIGS. 11 to 13.
[0084] As shown in FIG. 11, at a site at which a flow passage 60 of
a flow type microchip branches, the ultrasonic transducers disposed
respectively under the vicinity of the inlet of a branch flow
passage are individually driven by a predetermined signal. At this
time, a continuous wave set at a drive voltage whose frequency is
at a sufficiently shorter wavelength than flow passage dimensions
and is at a high radiation sound pressure is applied as a drive
signal. The ultrasonic wave radiated from the ultrasonic transducer
is a continuous wave whose frequency is at a sufficiently shorter
wavelength than the flow passage dimensions. Thus, as shown in FIG.
12, an acoustic flow is generated in a bi-directional manner
between an acoustic radiation surface and a flow passage wall
opposed thereto. At the same time, since a high radiation sound
pressure is obtained, this site becomes an obstacle to fluid
movement.
[0085] For example, if a transducer 662 shown in FIG. 12 is driven
as described previously, the fluid movement from the inlet 62 can
be inhibited by the transducer 66.sub.2. As a result, a switch
valve for feeding a fluid from the inlet 62 to only an outlet 64a
can be obtained as shown in FIG. 13. Further, an ultrasonic
transducer disposed immediately beneath one flow passage is driven
at a short wavelength and at a high radiation sound pressure, so
that an on/off valve can be achieved.
[0086] A radiation sound pressure is changed by setting of a drive
voltage value, thereby making it possible to achieve a valve which
enables flow rate adjustment.
[0087] Moreover, as shown in FIG. 14, the present invention can be
applied in the case of the flow passage 60 having the two inlets
62a and 62b and one outlet 64. That is, in the case where the fluid
from the two inlets 62a and 62b is a microchip joining in the main
flow passage 60, the valve transducers 66.sub.1 and 66.sub.2 are
driven alternately for a predetermined time, thereby making it
possible to quantify each fluid, as shown in FIG. 15.
[0088] As described above, by means of the ultrasonic transducer
disposed immediately beneath the flow passage, a distribution of
sound pressure strengths can be locally generated, so that it is
possible to generate a resistance against the flow of the fluid at
a portion at which the distribution occurs. In this manner, the
function of "valve" capable of turning on/off the fluid and
carrying out flow rate adjustment, quantification and the like can
be achieved.
[0089] In the microchip which achieves the first or second function
described previously, the transducers may be disposed at the upper
part, at the lower part, at the left or right, or at one side or
both sides of the flow passage as long as the distribution of
desired sound pressure strengths can be generated in a direction in
which the fluid flows, and its disposition and number are not
limited.
[0090] Now, an operation of the "temperature gauge" which is the
third function will be described with reference to FIGS. 16 to
19.
[0091] In this case, immediately beneath a flow passage 70 having
one inlet 72 and one outlet 74, a wave transmission ultrasonic
transducer 76.sub.1 serving as ultrasonic wave transmission means
is disposed in the vicinity of the inlet 72, and a wave reception
ultrasonic transducer 76.sub.2 serving as ultrasonic wave reception
means is disposed in the vicinity of the outlet 74.
[0092] The wave transmission ultrasonic transducer 76.sub.1
provided at the lower part at the inlet 72 side of the flow passage
70 of the flow type microchip shown in FIG. 16 is driven by means
of a tone burst wave. As shown in FIG. 17, the wave-transmitted
tone burst wave is sent from the inlet 72 to the outlet 74 while
the wave is attenuated. Then, the resulting wave is sensed by the
wave reception ultrasonic transducer disposed to be spaced by a
predetermined distance L, and the wave reception ultrasonic
transducer outputs an output signal capable of discriminating that
an ultrasonic wave has been received.
[0093] As shown in FIG. 18, when a time difference from wave
transmission at the wave transmission ultrasonic transducer
76.sub.1 to sound wave sensing by the wave reception ultrasonic
transducer 76.sub.2 is defined as .DELTA.T, the following formula
is generally established: U+c(t)=L/.DELTA.T (1) wherein U is a flow
velocity of a fluid, and "c" is a sound velocity of a fluid
imparted by a function of a temperature "t".
[0094] That is, if the distance L, the flow velocity U, and
function of "c(t)" indicating a relationship between a temperature
and a sound velocity of a fluid are known, the sound velocity value
"c" obtained by Formula (1) above is inputted to the function of
"c(t)", whereby the temperature "t" can be obtained. Therefore, by
using two ultrasonic transducers disposed under the flow passage at
a predetermined distance, the foregoing processing is carried out
by a signal processor circuit layer, thereby making it possible to
achieve the function of "temperature gauge" for measuring a fluid
temperature.
[0095] Even if a flow rate (Q) is defined instead of the flow
velocity U, a similar result can be obtained.
[0096] Now, an operation of the "mixer" which is the fourth
function will be described with reference to FIG. 20.
[0097] For example, in a flow passage 80 having two inlets 82a and
82b and one outlet 84, a liquid housing cell 86 which is greater
than a flow passage width is provided on a flow passage of a
microchip. In addition, a plurality of ultrasonic transducers
88.sub.(1, 1), 88.sub.(1, 2), . . . , 88.sub.(1, n), . . . ,
88.sub.(m, 1), . . . , 88.sub.(m, n) formed in a two-dimensional
matrix shape are disposed under the liquid housing cell 86.
Further, a valve transducer 90 for an optical absorption gauge is
disposed at the downstream side of the plurality of two-dimensional
matrix shaped ultrasonic transducers 88.sub.(1, 1) to 88.sub.(m,
n).
[0098] Now, assume that predetermined drive signals are supplied in
irregular sequence to the plurality of ultrasonic transducers
disposed in the two-dimensional matrix shape under the liquid
housing cell. As has been explained as for the function of "pump"
described previously, with respect to the ultrasonic wave radiated
from each of the ultrasonic transducers, an acoustic flow (straight
flow) is generated in a direction distant from a sound source in
accordance with its non-linearity, but the acoustic flow is bent in
a direction in which a sound pressure is high due to a balance in
sound pressure strength of the adjacent transducers. Thus, the
transducers each are driven in irregular sequence, whereby a
distribution of sound pressure strengths is changed with an elapse
of time. Then, at a portion at which the distribution changes, it
is possible to form a respective different complicated flow field
at each time, for example, a flow field in which there occurs a
flow in a direction crossing an interface between fluids in a
plurality of different physical properties or states, the fluids
being introduced from the two inlets 82a and 82b, or there occur
flows in directions opposed to each other in the fluids. Therefore,
the "mixer" for stirring and mixing the liquid contained in the
liquid housing cell can be achieved by optimally driving the
ultrasonic transducers disposed in the two-dimensional matrix
shape.
[0099] As shown in FIG. 20, the function of "valve" is added more
downstream of the function of "mixer", thereby making it possible
to stir and mix the fluid to be stirred in the liquid housing cell
in a state in which the fluid has been maintained.
[0100] While the first embodiment has described that stirring is
carried out in a liquid housing cell capable of generating a more
complicated flow, stirring may be carried out in a flow passage. If
the distribution of the sound pressure strengths can be changed
with an elapse of time, disposition of the ultrasonic transducers
is not limited onto the two-dimensional matrix. In addition, it is
not necessarily to move the transducers in irregular sequence, and
a complicated flow may be generated by changing the sound pressure
strength near the at least one ultrasonic wave transmission means
and the sound pressure strength near the remaining ultrasonic wave
transmission means.
[0101] In the meantime, in the first embodiment, an optical
absorption gauge is further configured at the downstream side of
the function of "mixer". Now, an operation of the optical
absorption gauge using a photodiode will be described with
reference to FIGS. 21 and 22.
[0102] Although not shown in FIG. 21, predetermined light is
irradiated toward the microchip flow passage 80 from a light source
installed to be distant upwardly of the flow type microchip flow
passage. Then, the light having transmitted the microchip flow
passage 80 is detected by the photodetector 32 provided in the
signal control circuit layer 12.
[0103] With respect to a predetermined wavelength of the light
detected by the photodetector 32, its light intensity is compared
with that of an input light, whereby an absorption rate at the
predetermined wavelength can be obtained in the signal control
circuit layer 12.
[0104] In the above first embodiment, the fluid control step of
quantifying, stirring, and mixing two reagents and one sample while
monitoring a fluid temperature is achieved with only a combination
of the arbitrary ultrasonic transducers in the transducer layer of
the common platform, and optimal absorption measurement is achieved
by the chemical analysis system utilizing the signal processing
layer of the common platform.
[0105] An ultrasonic platform type micro chemical analysis system
can be separately fabricated in accordance with each silicon
process and resin processing with respect to the common platform
and microchip. Thus, in this system, the standardized common
platform can be manufactured in accordance with the silicon process
while general purpose usability, quick responsiveness, and
functional upgrading property required for the microchip are
maintained without losing a variety of advantages represented by a
liquid layer microspace, so that a short manufacturing time and low
cost can be achieved. Further, there is no need for changing a
fluid composition in the embodiment.
[0106] Further, in this system, there is no need for configuring a
complicated fluid control element (such as a valve) on a microchip.
Moreover, a function required for fluid control can be achieved
merely by optimally controlling a frequency or amplitude, or
alternatively, a irradiation time or irradiation time interval of
an ultrasonic wave irradiated by signal control of the ultrasonic
transducer in the common platform according to the purpose of the
microchip.
[0107] Constituent elements according to the first embodiment, of
course, can be variously modified or changed.
[0108] For example, the flow passage on the microchip can be
properly changed according to its purpose. In addition, the number
of fluid control elements is not limited to four shown in the
embodiment, and many more fluid control elements may be achieved or
one element may be achieved in one common platform.
[0109] In the microchip achieving the first or second function,
transducers may be disposed at the upper part, at the lower part,
at the right or left, at one side, or at both sides of a flow
passage as long as a distribution of desired sound pressure
strengths can be generated in a direction in which a fluid flow.
The disposition of the transducers is not limited to a position
immediately beneath the flow passage or both of the outside of the
flow passage.
[0110] The signal control circuit formed in accordance with the
semiconductor process may be CMOS, bipolar, a photodiode, by-CMOS
or the like.
[0111] Further, the transducer layer and the signal control circuit
layer in the common platform may be assembled by means of bonding,
adhesive or the like while conductivity is established, after
separately fabricated.
[0112] The system can be also configured such that the temperature
gauge transducer 22c shown in FIG. 3 has been replaced with a flow
velocity transducer 22e as shown in FIG. 23.
[0113] In more detail, if a distance L, a fluid type, and a
temperature "t" are known by utilizing the fact that a sound
velocity "c" is a sound velocity of a fluid imparted by a function
of the temperature "t", the sound velocity "c(t)" at that
temperature can be obtained as shown in FIG. 24. The flow velocity
U can be obtained from the foregoing formula (1). Therefore, by
using two ultrasonic transducers disposed under a flow passage at a
predetermined distance, the forgoing processing is carried out by
the signal processor circuit layer, thereby making it possible to
achieve the function of "flow velocity gauge" for measuring a flow
velocity of a fluid.
[0114] A configuration may be provided so as to measure a frequency
of an output signal, a difference in frequency between a drive
(input) signal and an output signal or strength of an input or
output signal according to the strength of ultrasonic wave, and a
difference in strength between the drive signal and the output
signal apart from a time difference from wave transmission to wave
reception (sound wave sensing), i.e., a time difference between an
inputted drive signal and an output signal from wave reception
means. For example, it is possible to easily make control so as to
obtain a desired sound pressure distribution by configuring a
control system for measuring a signal according to the received
ultrasonic wave and controlling an input signal based on the
measured signal. Consequently, it becomes possible to make precise
fluid control.
[0115] The foregoing ultrasonic transducer may be used as
ultrasonic wave transmission and reception means compatible with
ultrasonic wave transmission means and ultrasonic wave reception
means. Further, a configuration may be provided so as to enable
switching of functions serving as ultrasonic wave transmission
means and a function serving as ultrasonic wave reception means
according to time, purpose, and position.
[0116] The ultrasonic transducer may be a piezoelectric thick film
or a piezoelectric thin film fabricated in accordance with an
ejection deposition technique, a sol-gel synthesis technique, a
water and heat synthesis technique, a sputtering technique, a print
technique or the like without being limited to cMUT, and may be
achieved by polishing a bulk-shaped piezoelectric material.
[0117] Further, as shown in FIG. 25, the transducer layer 14 may be
configured so as to come into direct contact with a flow passage 28
of a flow type microchip 18a.
[0118] Furthermore, as shown in FIG. 26, a portion between the
transducer layer 14 and the flow passage 28 of the flow type
microchip 18a may be composed of an acoustic matched material
(acoustic matched layer 34). The acoustic matched layer 34 may be
porous silicon which is made porous due to anode synthesis of
silicon, the flow type microchip itself may be composed of a resin
which can be obtained as an acoustic matched layer, or an adhesive
agent of fixing the flow type microchip 18a to the common platform
16 may be compatible with the acoustic matched layer.
[0119] In addition, as shown in FIG. 27, an acoustic lens 94 may be
provided between the transducer layer 14 and the flow passage 28 of
the flow type microchip 18. In this manner, if the acoustic lens 94
is configured, it becomes possible to strengthen nonlinear effect
of an ultrasonic wave at a predetermined position.
[0120] Now, a second embodiment according to an ultrasonic platform
type micro chemical analysis system of the present invention will
be described with reference to FIG. 28.
[0121] A basic configuration of a common platform and a flow type
microchip in the second embodiment is identical to that of the
ultrasonic platform type micro chemical analysis system according
to the first embodiment described previously. However, this
configuration achieves an object by arbitrarily combining a
plurality of common platforms divided by the same type of fluid
measurement control element.
[0122] In FIG. 28, a first common platform 110a is configured to
have a plurality of flow passages 100 each having a reagent inlet
42, pump transducers 22a which correspond to the flow passages 100,
and flow velocity gauge transducers 22e. Similarly, a second common
platform 110b is configured to have a plurality of flow passages
102 each having a sample inlet 44, pump transducers 22a which
correspond to the flow passages 102, and flow velocity gauge
transducers 22e.
[0123] Third common platforms 112.sub.1 to 112.sub.5 each are
configured to have: a flow passage 104 having an inlet for the
first common platform 110a, an inlet for the second common platform
110b, and one outlet 46; valve transducers 22b, mixing (mixer)
transducers 22d; and a photo detector 32.
[0124] The third common platforms 112.sub.1 to 112.sub.5 are
prepared in number which corresponds to the number of the flow
passages 100 and 102 of the first and second common platforms 110a
and 110b. For example, as shown in FIG. 28, if the above flow
passages 100 and 102 each are five in number in this microchip, a
total of five platforms, i.e., the third common platforms 112.sub.1
to 112.sub.5 each having the flow passage 104 which has two inlets
are combined with each other for each flow passage.
[0125] In the second embodiment, the function of "pump", the
function of "flow velocity gauge", the function of "mixer", and the
function of "valve" are incorporated. A variety of these functions
bring about an operation and advantageous effect identical to those
of the first embodiment described previously.
[0126] The second embodiment is effective in the case where a large
amount of fluid has been processed in accordance with the same
steps, and specifically, can be applied to a chemical synthesis
pant or the like.
[0127] Constituent elements according to the second embodiment, of
course, can be various modified and changed.
[0128] For example, the flow passage on the microchip can be
properly changed according to its purpose. In addition, many more
fluid control elements may be achieved without being limited to the
four fluid control elements shown in the second embodiment.
[0129] Now, a function of "viscosity gauge" in a third embodiment
according to the present invention will be described with reference
to FIG. 29.
[0130] A basic configuration of a common platform and a flow type
microchip in the third embodiment is identical to that of the
ultrasonic platform type micro chemical analysis system according
to the first embodiment described preciously, and is different
therefrom in that an ultrasonic viscosity gauge is configured as a
fluid control element.
[0131] The ultrasonic viscosity gauge according to the third
embodiment is composed of: an transducer 106 (thick slide type or
SAW type) which vibrates in parallel to a flow passage 100 of a
flow type microchip; a resonator circuit including an ultrasonic
transducer as one element of the resonator circuit, although not
shown in FIG. 29; and a signal control circuit for detecting
viscosity of a fluid from a frequency change of the resonator
circuit.
[0132] Now, an operation of the third embodiment will be described
here.
[0133] If, like a SAW, an ultrasonic device for generating a
surface acoustic wave is vibrated in contact with a fluid, a load
according to its viscosity is applied to the ultrasonic transducer,
and thus, a nominal resonation frequency is lowered. On the other
hand, the ultrasonic device has a direct current resistance
component, a coil component, and a capacitance component like an
equivalent circuit. Accordingly, a resonator circuit can be
configured by combining it with another electrical element such as
a capacitor.
[0134] Consequently, by monitoring an output of the resonator
circuit, the lowering of the resonance frequency of the ultrasonic
transducer can be acquired in real time.
[0135] In the third embodiment, the resonator circuit is provided
as a circuit of the signal control circuit layer in the common
platform (for example, the processor circuit 20 in FIG. 11). For
this reason, it is possible to achieve the function of "viscosity
gauge" as a fluid control element of the ultrasonic platform type
micro chemical analysis system.
[0136] FIG. 30 is a view showing an example of a configuration of
the ultrasonic platform type micro chemical analysis system
according to the third embodiment.
[0137] In FIG. 30, a first common platform 114a is configured to
have: a flow passage 100 having a reagent inlet 42; pump
transducers 22a which correspond to the flow passage 100; flow
velocity gauge transducers 22e; and a viscosity gauge transducer
22f. Similarly, a second common platform 114b is configured to
have: a flow passage 102 having a sample inlet 44; pump transducers
22a which correspond to the flow passage 102; flow velocity gauge
transducers 22e; and a viscosity gauge transducer 22f.
[0138] In addition, a third common platform 116 is configured to
have: a flow passage 104 having an inlet for the first common
platform 114a, an inlet for the second common platform 114b, and
one outlet 46; valve transducers 22b; mixing (mixer) transducers
22d; and a photodetector 32.
[0139] Constituent elements according to the third embodiment, of
course, can be modified and changed.
[0140] Now, a fourth embodiment according to an ultrasonic platform
type micro chemical analysis system of the present invention will
be described with reference to FIG. 1.
[0141] A basic configuration of the fourth embodiment is identical
to that of the ultrasonic platform type micro chemical analysis
system according to the first embodiment described previously. In
this configuration, however, a transducer layer and a signal
control circuit layer in a common platform each are fabricated on
individual substrates, and these layers are assembled by adhesive
or bonding in a state in which the conductivity of each layer has
been established.
[0142] This configuration is effective in the case where the signal
control circuit cannot be compatible with high temperature
processing required for increasing processing precision of the
transducer layer. For example, although high temperature durability
of a CMOS circuit is in order of about 20.degree. C. in general,
there is a case in which a higher temperature is required for
improving the fine processing precession of the ultrasonic
transducer.
[0143] In this case, the transducer layer and the signal control
circuit layer are fabricated on individual circuits, whereby it is
possible to improve a substrate property of the transducer layer
such as making it possible to finely generate the transducer
without damaging the signal control circuit.
[0144] From the specific embodiments described previously, the
inventions having the following configurations can be
excerpted.
[0145] (1) A flow passage device comprising:
[0146] a flow passage in which a fluid flows; and
[0147] ultrasonic wave transmission means for irradiating an
ultrasonic wave to the fluid contained in the flow passage in a
direction which is different from a direction in which the fluid
flows, and producing a distribution of sound pressure strengths in
the direction in which the fluid flows.
[0148] (2) A flow passage device comprising:
[0149] a flow passage in which a fluid flows; and
[0150] a plurality of ultrasonic wave transmission means disposed
along a direction in which the fluid flows so as to irradiate an
ultrasonic wave to the fluid contained in the flow passage and to
produce a distribution of sound pressure strengths in the
direction.
[0151] (3) A flow passage device comprising:
[0152] a flow passage in which a fluid flows; and
[0153] ultrasonic wave transmission means disposed so as to
irradiate an ultrasonic wave to the fluid contained in the flow
passage in a direction which is different from a direction in which
the fluid flows,
[0154] wherein the fluid is controlled by generating a distribution
of sound pressure strengths of the ultrasonic wave in the direction
in which the fluid flows.
[0155] (4) A fluid control apparatus set forth in the above item
(3), wherein, by locally generating a distribution of the sound
pressure strengths, a resistance against the flow of the fluid is
generated at a portion at which the distribution occurs.
[0156] (5) A fluid control apparatus set forth in the above item
(3), wherein a desired distribution of the sound pressure strengths
is generated by controlling a frequency or an amplitude, or
alternatively, an irradiation time or an irradiation time interval
of the ultrasonic wave irradiated.
[0157] (6) A fluid control apparatus set forth in the above item
(4), wherein a desired distribution of the sound pressure strengths
is generated by controlling a frequency or an amplitude, or
alternatively, an irradiation time or an irradiation time interval
of the ultrasonic wave irradiated.
[0158] (7) A fluid control apparatus set forth in the above item
(3), wherein the ultrasonic wave transmission means is ultrasonic
wave transmission means for transmitting an ultrasonic wave in
response to an inputted drive signal,
[0159] the apparatus further comprising ultrasonic wave reception
means disposed to be spaced from the ultrasonic wave transmission
means at a predetermined distance, the reception means receiving
the transmitted ultrasonic wave to convert the received ultrasonic
wave to an output signal.
[0160] (8) A fluid control apparatus set forth in the above item
(7), wherein the ultrasonic wave reception means outputs an output
signal capable of discriminating that an ultrasonic wave has been
received.
[0161] (9) A fluid control apparatus set forth in the above item
(7), wherein the ultrasonic wave reception means outputs an output
signal in response to strength of the received ultrasonic wave.
[0162] (10) A fluid control apparatus set forth in the above item
(7), wherein the ultrasonic wave reception means is compatible with
ultrasonic wave transmission means.
[0163] (11) A fluid control apparatus set forth in the above item
(3), wherein the ultrasonic wave reception means is an ultrasonic
wave transducer which converts an electrical signal and an
ultrasonic wave to each other, and
[0164] the ultrasonic wave transducer configures part of a
resonator circuit and is capable of detecting a change of a
resonance frequency of the resonator circuit.
[0165] (12) A fluid control apparatus comprising:
[0166] a flow passage in which a fluid flows; and
[0167] a plurality of ultrasonic wave transmission means for
irradiating an ultrasonic wave to the fluid contained in the flow
passage, the transmission means being disposed along a direction in
which the fluid flows,
[0168] wherein the fluid is controlled by generating a distribution
of sound pressure strengths of the ultrasonic wave in the direction
in which the fluid flows.
[0169] (13) A fluid control apparatus set forth in the above item
(12), wherein, by locally generating a distribution of the sound
pressure strengths, a resistance against the flow of the fluid is
generated at a portion at which the distribution occurs.
[0170] (14) A fluid control apparatus set forth in the above item
(12), wherein sound pressure strength near at least one of the
ultrasonic wave transmission means is different from sound pressure
strength near the remaining ultrasonic wave transmission means.
[0171] (15) A fluid control apparatus set forth in the above item
(12), wherein a distribution of the sound pressure strengths is
changed with an elapse of time, thereby stirring the fluid at a
portion at which the distribution changes.
[0172] (16) A fluid control apparatus set forth in the above item
(12), wherein the fluid is composed of a plurality of different
physical properties or states, and
[0173] the plurality of fluids are stirred by generating a
distribution of the sound pressure strengths, and by generating a
flow in a direction crossing an interface of the plurality of
fluids in at least one fluid.
[0174] (17) A fluid control apparatus set forth in the above item
(12), wherein a desired distribution of the sound pressure
strengths is generated by controlling a frequency or an amplitude,
or alternatively, an irradiation time or an irradiation time
interval of the ultrasonic wave irradiated.
[0175] (18) A flow control apparatus set forth in any one of the
above items (13) to (16), wherein a desired distribution of the
sound pressure strengths is generated by controlling a frequency or
an amplitude, or alternatively, an irradiation time or an
irradiation time interval of the ultrasonic wave irradiated.
[0176] (19) A fluid control apparatus set forth in the above item
(12), wherein a voltage applied to at least one of the ultrasonic
wave transmission means is different from a voltage applied to the
remaining ultrasonic wave transmission means.
[0177] (20) A fluid control apparatus set forth in the above item
(12), wherein the ultrasonic wave transmission means is ultrasonic
wave transmission means for transmitting an ultrasonic wave in
response to an input drive signal,
[0178] the fluid control apparatus further comprising ultrasonic
wave reception means disposed to be spaced from the ultrasonic wave
transmission means at a predetermined distance, the reception means
receiving the transmitted ultrasonic wave to convert the received
wave to an output signal.
[0179] (21) A fluid control apparatus set forth in the above item
(20), wherein the ultrasonic wave reception means outputs an output
signal capable of discriminating that an ultrasonic wave has been
received.
[0180] (22) A fluid control apparatus set forth in the above item
(20), wherein the ultrasonic wave reception means outputs an output
signal in response to strength of the received ultrasonic wave.
[0181] (23) A fluid control apparatus set forth in the above item
(22), wherein the ultrasonic wave reception means is compatible
with ultrasonic wave transmission means.
[0182] (24) A fluid control apparatus set forth in the above item
(12), wherein the ultrasonic wave reception means is an ultrasonic
wave transducer which converts an electrical signal and an
ultrasonic wave to each other, and
[0183] the ultrasonic transducer configures part of a resonator
circuit and is capable of detecting a change of a resonance
frequency of the resonator circuit.
[0184] According to the present invention, there can be provided:
an ultrasonic platform type microchip which can be manufactured
within a short manufacturing time and at a low cost while
maintaining general purpose usability, quick responsiveness, and
functional upgrading property without changing a fluid composition
and losing a variety of advantages represented by a liquid layer
microspace; and a method of driving array-shaped ultrasonic
transducers.
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